V/L Effect on Vapor Pressure Measurement of Full Boiling Range Fuels Using the Two-Part Injection Method Ford Motor Company

Format:

Conference/Event

Author/Creator:

Lavoie, G.A., author.

Conference Name:

International Congress & Exposition (1993-03-01 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 1993

Summary:

The internally programmed two-injection method for determining the dissolved air correction in the CCA-VP laboratory vapor pressure instrument (Grabner Instruments), while adequate for pure, single component liquids, can be in error for full boiling range automotive fuels. For these fuels, errors of up to 10 kPa (1.5 psi) in vapor pressure at 38°C (100°F) can occur due to the increase in vapor pressure between the first and second injection caused by decreasing vapor liquid ratio (V/L); this increase is interpreted by the instrument as additional dissolved air and results in overcorrection for this effect. A method is demonstrated for removing the V/L effect using two TV/L values for the subject fuel, either calculated or measured independently. The true air correction determined in this way is similar to values obtained for single component fuels and to values calculated directly from air solubility data. It is emphasized that RVPE measurements (Reid Vapor Pressure Equivalent), obtained by the instrument (and other mini-method devices) are not affected by this correction since the air contribution is accounted for by an empirical correlation equation

Notes:

Vendor supplied data

Publisher Number:

930378

Access Restriction:

Restricted for use by site license